Calibration-Free Pulse Oximetry Based on Two Wavelengths in the Infrared — A Preliminary Study
The assessment of oxygen saturation in arterial blood by pulse oximetry (SpO2) is based on the different light absorption spectra for oxygenated and deoxygenated hemoglobin and the analysis of photoplethysmographic (PPG) signals acquired at two wavelengths. Commercial pulse oximeters use two wavelen...
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| Format: | Article |
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MDPI AG
2014-04-01
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| Series: | Sensors |
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| Online Access: | http://www.mdpi.com/1424-8220/14/4/7420 |
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| author | Meir Nitzan Salman Noach Elias Tobal Yair Adar Yaacov Miller Eran Shalom Shlomo Engelberg |
| author_facet | Meir Nitzan Salman Noach Elias Tobal Yair Adar Yaacov Miller Eran Shalom Shlomo Engelberg |
| author_sort | Meir Nitzan |
| collection | DOAJ |
| description | The assessment of oxygen saturation in arterial blood by pulse oximetry (SpO2) is based on the different light absorption spectra for oxygenated and deoxygenated hemoglobin and the analysis of photoplethysmographic (PPG) signals acquired at two wavelengths. Commercial pulse oximeters use two wavelengths in the red and infrared regions which have different pathlengths and the relationship between the PPG-derived parameters and oxygen saturation in arterial blood is determined by means of an empirical calibration. This calibration results in an inherent error, and pulse oximetry thus has an error of about 4%, which is too high for some clinical problems. We present calibration-free pulse oximetry for measurement of SpO2, based on PPG pulses of two nearby wavelengths in the infrared. By neglecting the difference between the path-lengths of the two nearby wavelengths, SpO2 can be derived from the PPG parameters with no need for calibration. In the current study we used three laser diodes of wavelengths 780, 785 and 808 nm, with narrow spectral line-width. SaO2 was calculated by using each pair of PPG signals selected from the three wavelengths. In measurements on healthy subjects, SpO2 values, obtained by the 780–808 nm wavelength pair were found to be in the normal range. The measurement of SpO2 by two nearby wavelengths in the infrared with narrow line-width enables the assessment of SpO2 without calibration. |
| first_indexed | 2024-12-10T06:22:59Z |
| format | Article |
| id | doaj.art-4e49631f0c7c411b812174556d9baa8b |
| institution | Directory Open Access Journal |
| issn | 1424-8220 |
| language | English |
| last_indexed | 2024-12-10T06:22:59Z |
| publishDate | 2014-04-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Sensors |
| spelling | doaj.art-4e49631f0c7c411b812174556d9baa8b2022-12-22T01:59:16ZengMDPI AGSensors1424-82202014-04-011447420743410.3390/s140407420s140407420Calibration-Free Pulse Oximetry Based on Two Wavelengths in the Infrared — A Preliminary StudyMeir Nitzan0Salman Noach1Elias Tobal2Yair Adar3Yaacov Miller4Eran Shalom5Shlomo Engelberg6Department of Applied Physics/Medical Engineering, Jerusalem College of Technology, Jerusalem 9116001, IsraelDepartment of Applied Physics/Medical Engineering, Jerusalem College of Technology, Jerusalem 9116001, IsraelDepartment of Applied Physics/Medical Engineering, Jerusalem College of Technology, Jerusalem 9116001, IsraelDepartment of Applied Physics/Medical Engineering, Jerusalem College of Technology, Jerusalem 9116001, IsraelDepartment of Applied Physics/Medical Engineering, Jerusalem College of Technology, Jerusalem 9116001, IsraelDepartment of Applied Physics/Medical Engineering, Jerusalem College of Technology, Jerusalem 9116001, IsraelDepartment of Electronics, Jerusalem College of Technology, Jerusalem 9116001, IsraelThe assessment of oxygen saturation in arterial blood by pulse oximetry (SpO2) is based on the different light absorption spectra for oxygenated and deoxygenated hemoglobin and the analysis of photoplethysmographic (PPG) signals acquired at two wavelengths. Commercial pulse oximeters use two wavelengths in the red and infrared regions which have different pathlengths and the relationship between the PPG-derived parameters and oxygen saturation in arterial blood is determined by means of an empirical calibration. This calibration results in an inherent error, and pulse oximetry thus has an error of about 4%, which is too high for some clinical problems. We present calibration-free pulse oximetry for measurement of SpO2, based on PPG pulses of two nearby wavelengths in the infrared. By neglecting the difference between the path-lengths of the two nearby wavelengths, SpO2 can be derived from the PPG parameters with no need for calibration. In the current study we used three laser diodes of wavelengths 780, 785 and 808 nm, with narrow spectral line-width. SaO2 was calculated by using each pair of PPG signals selected from the three wavelengths. In measurements on healthy subjects, SpO2 values, obtained by the 780–808 nm wavelength pair were found to be in the normal range. The measurement of SpO2 by two nearby wavelengths in the infrared with narrow line-width enables the assessment of SpO2 without calibration.http://www.mdpi.com/1424-8220/14/4/7420oxygen saturationpulse oximetryinfraredarterial blooddiode laserscalibration |
| spellingShingle | Meir Nitzan Salman Noach Elias Tobal Yair Adar Yaacov Miller Eran Shalom Shlomo Engelberg Calibration-Free Pulse Oximetry Based on Two Wavelengths in the Infrared — A Preliminary Study Sensors oxygen saturation pulse oximetry infrared arterial blood diode lasers calibration |
| title | Calibration-Free Pulse Oximetry Based on Two Wavelengths in the Infrared — A Preliminary Study |
| title_full | Calibration-Free Pulse Oximetry Based on Two Wavelengths in the Infrared — A Preliminary Study |
| title_fullStr | Calibration-Free Pulse Oximetry Based on Two Wavelengths in the Infrared — A Preliminary Study |
| title_full_unstemmed | Calibration-Free Pulse Oximetry Based on Two Wavelengths in the Infrared — A Preliminary Study |
| title_short | Calibration-Free Pulse Oximetry Based on Two Wavelengths in the Infrared — A Preliminary Study |
| title_sort | calibration free pulse oximetry based on two wavelengths in the infrared a preliminary study |
| topic | oxygen saturation pulse oximetry infrared arterial blood diode lasers calibration |
| url | http://www.mdpi.com/1424-8220/14/4/7420 |
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